C++ interface for matplotlib

Question

I was wondering if there's an interface to matplotlib that can be used from C++. (Perhaps something similar to what gnuplot has)

Answer 1

It is old question, but there is C++ api to use Mathplot: matplotlib-cpp developed from 2014

Answer 2

Based on this SO question, you can use strings:

For static data, it's really easy:

#include "Python.h"

int main()
{
   Py_Initialize();
   PyRun_SimpleString("import pylab");
   PyRun_SimpleString("pylab.plot(range(5))");
   PyRun_SimpleString("pylab.show()");
   Py_Exit(0);
   return 0;
}

It gets a bit more tricky, but still possible with variable data, just concatenate it to a string.

#include <string>
#include "Python.h"

using namespace std;

int main()
{
   Py_Initialize();
   int x[5] = {0, 1, 2, 3, 4};
   int y[5] = {5, 1, 7, 5, 1};
   string command = "pylab.plot([";
   for(int i = 0; i < 4; i++) {
       command += x[i];
       command += ", ";
   }
   command += x[4];
   command += "], [";
   for(int i = 0; i < 4; i++) {
       command += y[i];
       command += ", ";
   }
   command += y[4];
   command += "])";
   PyRun_SimpleString("import pylab");
   PyRun_SimpleString(command.c_str());
   PyRun_SimpleString("pylab.show()");
   Py_Exit(0);
   return 0;
}

(Please note that I didn't check this for bugs, so there may be some in there, but you get the idea, and yes, it's a very ugly solution).